Problem: Express your answer as a mixed number simplified to lowest terms. $17\dfrac{3}{5}-4\dfrac{1}{5} = {?}$
Separate the whole numbers from the fractional parts: $= {17} + {\dfrac{3}{5}} - {4} - {\dfrac{1}{5}}$ Bring the whole numbers together and the fractions together: $= {17} - {4} + {\dfrac{3}{5}} - {\dfrac{1}{5}}$ Subtract the whole numbers: $=13 + {\dfrac{3}{5}} - {\dfrac{1}{5}}$ Subtract the fractions: $= 13+\dfrac{2}{5}$ Combine the whole and fractional parts into a mixed number: $= 13\dfrac{2}{5}$